Exercise tolerance after anaemia correction with recombinant human erythropoietin in end-stage renal disease

The aim of this study was to evaluate the effect of correction of chronic anaemia on the physical performance and the cardiovascular response to effort in children with end-stage renal disease (ESRD) maintained by haemodialysis. Seven patients (mean age 13.9 years) underwent triangular-type treadmill exercise testing before [haemoglobin (Hb) 6.3 +/- 0.9 g/dl] and after (Hb 11.2 +/- 1.2 g/dl) anaemia correction with recombinant human erythropoietin (rHuEPO). After treatment, the work-load reached, the peak oxygen uptake and average ventilatory anaerobic threshold (VAT) values were significantly increased (P less than 0.01, P less than 0.001, P less than 0.05 respectively). VAT values, expressed as a percentage of normal values, increased from 55.7 +/- 16.6% to 82.4 +/- 21%. This improvement correlated well with the increase in Hb (r = 0.79). Oxygen pulse also increased significantly, when tested after anaemia correction. In conclusion, these data demonstrate that when the anaemia of children with ESRD is corrected with rHuEPO, there is a clear improvement in aerobic work capacity and effort tolerance.

Benefits and risks of anemia correction with recombinant human erythropoietin in children maintained by hemodialysis

Ten children with renal failure (age range 2 years 6 months to 18 years 9 months; median 11 years 10 months), maintained by long-term hemodialysis, had successful correction of their anemia after intravenous administration of recombinant human erythropoietin in a dosage escalating every 2 weeks (75 to 150 to 300 to 450 IU/kg/wk). Mean hemoglobin concentration increased from 6.4 +/- 0.9 to 11.5 +/- 1.0 gm/dl. Blood cell counts used to evaluate the correction of anemia were done after dialysis; this was especially important for children less compliant with water restriction. The higher hemoglobin concentration resulted in improvement of the quality of life, a greater tolerance for physical effort (exercise tolerance doubled and the ventilatory anaerobic threshold increased significantly), correction of some subclinical central nervous system abnormalities detected by evoked potentials testing, and reduction of bleeding time. Few side effects were noted; severe hypertension developed in one patient when postdialysis hematocrit was only 28%, and there were two episodes of hypertransaminasemia with no other evidence of liver dysfunction. We conclude that in children with renal failure the use of recombinant human erythropoietin to correct anemia is safe and strongly advisable, because of the resolution of many of the symptoms correlated with anemia.

[Clinical experience with a hydrolyzed soy formula in infants with protracted enteritis and atopic eczema]

A lactose-free soy and beef hydrolysate based formula ("Pregomin" Milupa) was studied in 12 infants affected with protracted enteritis and in 10 infants affected with atopic eczema. After 1 month of treatment with "Pregomin" an oral provocation test was performed using intact soy protein. The aim of this latter test was to evaluate if the hydrolysed soy formula could cause allergic sensitization to soy protein. We obtained the following results in the group of infants with enteritis: good catch-up growth, malnutrition laboratory test improvement, negative allergic tests, positive oral provocation test in only one infant who had been previously fed with intact soy protein. In the group with atopic eczema we found an improvement of the eczema, negative allergic tests, 3 out of 9 positive oral provocation tests (in infants previously fed with soy protein based formulas). Our data show that "Pregomin" formula was effective both from a gastroenterological point of view and from an allergological one. Furthermore we did not observe any positive oral provocation test with soy protein in infants who had never been exposed to this type of protein. The latter result seems to demonstrate that "Pregomin" formula does not possess any allergenic properties.

Effect of inhaled disodium cromoglycate and albuterol on energy cost of running in asthmatic children

The purpose of this study is to evaluate the effect of disodium cromoglycate and albuterol on energy cost of running, gas exchange, and ventilation during maximal exercise in children with exercise-induced asthma (EIA). Twelve children (7.1-15.5 years old) with a history of mild to moderate asthma and EIA performed three maximal exercise tests on a treadmill: 1) test A, without premedication; 2) test B, after premedication with inhaled disodium cromoglycate (DSCG) (40 mg); 3) test C, after premedication with inhaled albuterol (200 micrograms). The energy cost of running was calculated at each minute of exercise. None of the children were limited by dyspnea during the run. The post-exercise fall in FEVi after test A was greater than 20% for each child, the mean fall being 32.8 +/- 11.6%, in comparison with 12.6 +/- 8.9% after test B (P less than 0.001) and 2.5 +/- 5.3% after test C (P less than 0.001). There was no difference in the baseline oxygen uptake for the three tests. Maximum oxygen uptake (VO2 peak) decreased from 43.9 +/- 7.7 mL/min/kg in test A to 37.7 +/- 6.0 mL/min/kg in test B (P less than 0.01) and 39.1 +/- 7.2 mL/min/kg in test C (P less than 0.05). Ventilatory anaerobic threshold in tests B and C was significantly lower than in test A (P less than 0.01). Ventilation (L/min) and energy cost of running (O2 mL/kg/m) were significantly lower in tests B and C than in test A at comparable times. Running time was longer in B and C (P less than 0.05) with respect to A.(ABSTRACT TRUNCATED AT 250 WORDS)

Gas exchange during exercise in obese children

Twenty-three obese children, aged 9 to 14 years, ranging in percentage overweight from 26% to 83% (median 51.6% +/- 16.3%), and 37 normal-weight children, matched for sex, age and height, performed a maximal exercise test on a treadmill. Cardiorespiratory performance was assessed by determination of the ventilatory anaerobic threshold (VAT) expressed in ml O2/min per kg and as a percent of maximal oxygen uptake (% VO2max). VAT and VO2max related to body weight were significantly lower (P less than 0.01) in the obese than in the normal-weight children. VAT % VO2max was similar in the two groups. A significant correlation was found between VAT and VO2max both in the obese (r = 0.85) and in the control groups (r = 0.79). The habitual level of physical activity was lower in the obese subjects compared to the control subjects (P less than 0.001). In conclusion our study shows that physical fitness of overweight children is quantitatively lowered and that it can be assessed by VAT. VAT does not require a maximal test and is particularly useful in the ergometric study of subjects with exercise intolerance.

A comparison of two noninvasive methods in the determination of the anaerobic threshold in children

Seventy children, ranging in age from 7 to 14 years, performed a maximal exercise test on a treadmill with determination of the anaerobic threshold (AT) by two methods: (1) with the gas exchange method the ventilatory anaerobic threshold (VAT) was identified by the increase in the ventilatory equivalent for O2 uptake without a concomitant increase in the ventilatory equivalent for CO2 output and (2) with the method proposed by Conconi, the AT was taken at the point beyond which the increase in work intensity exceeded the increase in heart rate and the linearity of the work rate/heart rate relationship was lost. The AT values measured with the two methods were correlated (r = 0.80, P less than 0.001). This result confirms, also in children, the validity of the simple Conconi method: It can be used particularly for the determination of the individual optimal intensity of training.

Age-related changes in plasma dehydroepiandrosterone sulphate, cortisol, testosterone and free testosterone circadian rhythms in adult men

The circadian rhythms of serum luteinizing hormone, follicle-stimulating hormone, testosterone (T), free testosterone (fT), sex hormone-binding globulin (SHBG), oestradiol, cortisol and dehydroepiandrosterone sulphate (DHA-s) have been investigated in 5 normal male adults and 6 elderly men. Circadian rhythms were detected statistically significant (p less than 0.05) by population mean cosinor analysis, for T, fT, cortisol and DHA-s in the young group. In the elderly population, serum cortisol showed a clear circadian rhythm, although with some phase modification, whereas DHA-s secretion lost its circadian rhythmicity. This demonstrates that ageing differently affects the two major adrenal functions, glucocorticoid and androgenic; further, the data suggest that an independent adrenal androgen-regulating system could be selectively impaired in the older subjects. In the elderly group the loss of T circadian rhythm was confirmed, but a statistically significant circadian rhythm of fT was recorded. It was characterized by a marked phase advance and not related with the SHBG modifications found in elderly men. This finding leads us to reconsider the role of fT, which appears more sensitive than total T, in studying circadian rhythm of gonadal androgen secretion.

Antiepileptic drugs and puberty

This paper investigates pubertal development in 57 epileptic subjects, ranging in age from 6 to 15 years, under anti-epileptic therapy for at least 2 years. The results were compared with those from a control group of healthy volunteers. The onset of stage II puberty was significantly earlier in both male and female treated epileptics than in healthy control subjects: at this stage serum levels of 17-beta-estradiol (E2) were found to be significantly lower in treated epileptic females than in healthy control females and the serum levels of follicle-stimulating hormone (FSH) significantly lower in treated epileptic males than in control subjects. At stage III puberty, serum levels of FSH were significantly lower both in male and female treated epileptic than in healthy control subjects.